c^2 = a^2 + b^2 - 2(ab)(cos C)
c^2 + 2(ab)(cos C) = a^2 + b^2
2(ab)(cos C) = a^2 + b^2 - c^2
cos C = (a^2 + b^2 - c^2) / 2ab - Answer choice E
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The principal, real, root of:
=7.41619849
Answer:
He has 10 nickels and 5 dimes
Step-by-step explanation:
We can take advantage of the ratio by dividing 40 by 8, giving us that every 1 in the ratio = 5. So we can multiply 2 x 5 = 10 and 1 x 5 = 5.
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